How many crew sailed with Columbus in 1492?

How to get close to this number

Note that the question asks about crew, not ships. Three ships of that era each carried somewhere between twenty and forty men, and multiplying gives a total under a hundred. Reading which quantity is being asked for is half the work here, because the ship count is the famous number and the crew count is not.

The ship dimension in the explanation is what conveys the risk: the largest vessel was about nineteen metres long, shorter than a tennis court. Crossing an ocean of unknown width in a boat that size, with no way to determine longitude, is a scale of gamble that modern seafaring has no equivalent for.

The crossing time of thirty-six days from the Canaries is the other calibration. That is a long time to be out of sight of land with finite water, and it is why the departure point matters — sailing from the Canaries rather than from Spain shortened the open-ocean leg substantially and made the attempt survivable.